Indicating instrument



July 12, 1960 T. A. GREEN ETAL 2,945,120

INDICATING INSTRUMENT Original Filed July 28, 1950 INVENTORS THOMAS A. GREEN, HARVARD H. GORRIE,

AND JACK F. SHANNON TREVOR Fl K fiwL '7 Anomvm' niteci States INDICATING INSTRUMENT Thomas A. Green, Willoughby, Harvard H. Gorrie, Cleveland Heights, Jack F. Shannon, Euclid, and Trevor Fink, University Heights, Ohio, assignors to Bailey Meter Compmy, a corporation of Delaware Application June 10, 1954, Ser. No. 435,883, now Patent No. 2,885,536, dated May '5, 1959, which is a division of application Ser. No. 176,382, July 28, 1950. Divided and this application July 7, 1958, Ser. No. 747,025

5 Claims. (Cl. 240-521) Our unitary construction is not, however, restricted,

to vertical edgewise panel mounting. One widely acccpted usage is for table mounting on bench or console type control panels where the scale edge of the unit is horizontal or at a slight inclination with the horizontal and with most of the unit projecting beneath the bench or console top. 7

Furthermore, the unitary enclosed construction allows. the gauging-up or stacking of numerous units with the indicative scales parallel or end-to-en-d. On the other hand, the .unit may be incorporated in an assembly of.

metering or control apparatus to advantage.

While we have chosen to designate our invention a related to pressure gages, we so-name ageneral class without meaning to restrict the usefulness of the invention in the measurement'of other variable quantities, qualities, conditions, positions, or the like.

The principal object of our invention is to provide an indicating gage of unitary construction adapted for universal mounting or arrangement in multiple or with. other apparatus and having an arcuate scale,.a'reflector.

plate arranged in particular'angular relation to the scale, and a detachable source of illumination arranged to radiate onto thescale and the reflector plate.

A further object resides in providing an indicating gage having the scale, reflector, and illuminating source Patented July 12, 1960 ice ness. The shape is in general rectangular with a flat side mounting wall 21, top wall 22, bottom wall 24 and a rear wall 23. The near side is normally covered by a removable side plate 25 (Fig. 5) which may be held to the housing 20 by screws threadable into holes 26.

' For purposes of illustration the housing 20 of Fig. 1

has been sectioned slightly below the ledge (Fig. 5) which provides a resting place for the cover 25.

The housing 20has no fixed front wall (to the right as viewed in Fig. 1) but the opening is desirably closed by a molded transparent window 27 which may be of glass or a clear plastic. The latter is preferred as less susceptible to breakage through handling, vibration or shock. The window 27 is formed with a long radius protru-dent to the right (Fig. 1) beyond the limits of housing walls 21, 22, 24. The two sides 28 and 29 of window 27 extend rearwardly to join the forward edges of side wall 21 and of cover 25. Along the top a rearward projection '30, and along the bottom a similar projection 31, enter the confines of the housing as shown. The projection 31 is provided with a hole 32 which may be adapted to receive a spring end 33 as shown in Fig. l

or in the dotted position of Fig. 4. In similar manner the upper projection is provided with a hole receiving a more rigid spring end 34. Figs. 1 and 2 show the window 27 in its assembled location with projections 30 and 31 receiving the ends '33, 34 and thus holding the window tightly closing the end opening formed by the housing 20 and cover 25. Provision is made for easy assembly as well as for ready removal of the window, portion 27 for inspection and cleaning of the scale,

pointer, etc. Figs. 1 and 2 show the window in its assembled position. Fig. 4 is an enlarged detail of a lower right-hand portion of Fig. 1 illustrating the operationto be performed for removing or inserting window 27.

Referring now particularly to Fig. 4 the dot-dash out line to the left shows the window structure in the same assembled location as in Fig. 1. 'If it is desired to remove the window structure then a lifting screw 35 may be threaded upwardly through the tapped hole 36 of the 1 leaf spring 37 until the upper end of screw 35 engages adapted to the ready gauging or grouping of a pluralityof such instruments.

Another object is to provide an indicating receiver of substantially universal adaptability to difierent forms and having illuminating means including a light gathering reflector and a detachable source of illumination.

Still other objects will be apparent from .a study of. the drawings, the description thereof, and of our claims In the drawings: Fig. 1 is a sectional elevation of a single tube gage. Fig. 2 is a front face view of the assembly of Fig. 1. Fig. 3 is a view of a portion of the assembly of Fig. 1 taken along the line 33 in thedirection of the arrows. Fig. 4 is an enlarged view of that portion of Fig. l enclosed by dot-dash line and designated 4.

Fig. 5 is an exploded view of a portion of Fig. 1. Referring now in particular to Fig. 1, we show therein a side elevational view of our preferred apparatus as embodied in what is sometimes termed a vertical edgewise indicator. The housing 20 is formed as a die casting obtaining lightness, with rigidity, strength and dust ti-ght-- the fixed lower end of rivet 38. Continued threading of screw 35 into hole 36 flexes the right-hand end of spring 37 (around its pivot 39) downwardly thus withdrawing the pin end 33 from the hole 32 to a positionshown in solid line in Fig. 4.

Such withdrawal of the pin 33 from the hole 32 allows an operator, through grasping the lower portion of window 27, to move the lowermost projection 31 outwardly from the wall 24 until the pin 34 no longer engages the upper projection 30 and the window 27 is completely removed. It may be reinserted through a reverse operation of first engaging the hole in upper pro-- jection 30 with the pin 34 and then sliding the lower portion of the window inwardly until it completely closes the end cavity of the assembly. Thereafter a backing offof the screw 35 allows pin 33 to enter the hole 32 and lock the window in place. The screw 35 "may be left partially inserted in the cavity 36 or may be removed as is shown in Fig 1.

Referring again to Fig. 4 it will be seen that the rivet 38 serves additionally to hold the scaleplate assembly by engaging a projection 40 thereof. The scale plate 41 itself is'cunved to an arc corresponding to the travel of the indicating pointer and may be the same or slightly different than the outward surface are of the window 27. It is only essential to maintain sufiicient clearance between the pointer, scale plate 41 and inner surface of window 27, at the mid-travel position of the pointerf". The lowermost end of the scale plate 41 receives a rivet 42 holding to it a spring clip 43 eflectivel-y spacing the scale plate 41 [from the inner lower edge of the window housing. At the upper end of the scale plate 41 a similar spring clip 44 is provided as well as a projection 45 of the scale plate (similar to the projection 40). The pin clip 34 as well as the projection 45*are held by a rivet 46 to the top wall 22.

The forwardly arched scale plate 41 is recessed along its edges as at 47, 48 providing clearance paths for movable pointers. Centered along the arc face of the scale plate 41 is a raised scale portion 49 upon which are engraved or painted the scale graduations. Preferably the side portions 50, 51 contain information, relative to the scale graduations, of Service which may be flow, pressure, or the like; and of numerals 0, 10, 20, etc., relating to the Service and to the scale graduations.

Preferably the pointer end 52 (Fig. 2) travels over the depressed surface 58 (or 51) with clearance thereoverand withits indicating end adjacent to graduations on the elevated portion 49. As viewed in Fig. 1 it will be observed that the pointer 52 does not extend beyond the arc of the surface 49 and does not in any respect overlap the graduations or produce parallax in the reading gage.

In the present embodiment, illumination of the unit is accomplished by a recessed light bulb 53 mounted in top wall 22 behind the window 27 and scale plate 41. A light reflecting surface or wall may be formed by the bottom wall of a U-shaped member held in position by the rivet 42 and having side walls spaced from the side wall 21 and the inside of cover 25 to allow pointer travel. This substantially prevents light from the source 53 entering the housing surrounding shield 54 and minimizing eye viewing of working parts of the instrument behind the shield 54 througlrthc slots 47, 48. Normally the scale plate 41 may be of some translucent plastic or similar material upon which the graduations and other indicia are painted or engraved so that they will stand out in contrast to the lighted scale plate itself when the latter is illuminated by the source 53 and reflection from the surface 54.

The light source '53 may be held in a convenient socket assembly 55 having terminals 56 and the assembly is removably mounted in a clip 57 (Fig. having one or more locking prongs 58 engageable with the inner surface of a hole 59 formed in the upper wall 22 of the housing 29. The assembly is shown in Fig. 1 in its normal operation position wherein the prongs 58 are in engagement and a spring button 60 carried by the clip 57 is thus expanded through a hole 61 in the top of wall 22.

From the assembled position (Fig. 1) the assembly 53, 55, 56, 58, 60 cannot be loosened or pulled from the unit, in any direction except that shown by the arrow X of Fig. 5. In other words, any strain on 55 or 56, as by wires or conduit, toward the observer of Fig. l, or away from the observer, or toward the left, will not cause a pull-out of the assembly due to the gripping of wedge prongs 58; and those are the normal directions of undesired strains upon 55, i.e., away from the back of a panel through which the window 27 projects. Desi-red removal is, however, readily accomplished by pivoting the assembly toward the rear of the panelin the direction ofthe arrow X (Fig. 5).

' The operative or active element of our improved indicator is illustrated in Fig. 1 as a Bourdon tube 65 having one end permanently fastened to a base casting or forging 66 which is in turn held by screws 67 to the back 21 of the housing 20. All of the contents of the housing 20 are supported relative to the side plate 21 so that the cover 25 may readily be removed without disturbing any of the active elements which may continue: in operation.

The interior of the Bourdon tube 65 communicates with a passage 68 and the lower wall 24 is provided with a clearance opening 69 to allow pipe connection to the passage 68.

The free end of the Bourdon tube 65 is connected 4. through an element 70, connecting link 71 and U-shaped member 72 to angularly position the shaft 73. The shaft 73 is pivotally supported by an assembly held together by screws 81. One of the plates 80 has an extension 82 through which screws 83' pass into base 66 providing a rigid mounting for the shazft 73. Carried by the shaft 73, in addition to the U-shaped member 72, is an enlarged hub 73A and a toothed disc 79. Angular motion of the shaft 73, by the Bourdon tube 65, through the agency of elements 71 and 72, angularly moves the elements 73A and 79.

The pointer arm 74 has a weighted end portion 75 and the pointer arm assembly has a hole clearing the shaft 73. In Fig. 3 the pointer arm 74 and weight 75 are at the right of toothed disc 79 and carry a bracket 76 which spans the disc 79 to encircle the hub 73A on the left-hand side of disc 79. The bracket 76 is fastened to the pointer arm 74 by a rivet 76A.

Carried by the bracket 76, and engaging with the toothed disc 79 is a worm- 78 extending in a plane parallel to pointer arm 74. Turning of the worm 78 in the teeth of disc 79 angular-1y moves the assembly 52, '74, 75, 76, 76A, and 78 around the disc 79 and shaft 73. This provides a zero adjustment for the pointer 52 rela tive to the scale graduations 49 without movement of the shaft 73 or any of the elements which cooperate to angularly position the shaft under the dictates of the Bourdon tube 65. The bracket 76, between hub 73A and rivet 76A, locks worm 78 snugly into engagement with teeth 79 thereby eliminating error due to clearances required for manufacture and operation.

Carried also by the shaft 73 is one end of a hair spring 85, the other end being adjustably clamped as at 86 to an extension of a plate 80, for taking up lost motion of the assembly.

As previously mentioned the Bourdon tube 65 angularly positions the shaft 73 through the agency of an element 70, connecting link 71 and U.-shaped member 72.

The member 72 is fastened at one end to the shaft 73 at its other end carries an extension having a plurality of range holes through which we may selectively pass one end of the link 71. A screw 91 is threaded through an arm of the member 72 and has its end bearing against the other arm of the member in a hole or bearing dimple. Adjustment of the screw 91 serves to position the holes relative to the pivot 73 and to thus vary the distance relative to the length of the pointer arm. Thus the selective holes and the adjusting screw 91 provide a means for varying the range of pressure which must act upon the Bourdon tube 65 to accomplish a predetermined travel of the pointer 52 over the scale 49. Initial adjustment of screw 91 stresses the U member 72 toward an open position so that the screw is always tightly effective across the arms of the U.

Both the zero adjusting screw 78 and the range adjusting screw 91 are accessible through an opening 92 (Fig. I) normally covered by a clip 93 held in place by the spring plug 94.

At this point we mayobserve that the system being described is equally applicable to the measurement and indication of either positive pressures or of negative pressures. In the latter case it may be desirable to turn the unit upside down and reverse the scale which would then be graduated from zero to whatever negativepressure were desired for total movement of the pointer 52.

After the pointer arm assembly is statically and dynamically balanced it is mounted in the unit, and, with the unit in a vertical position (Figs. 1 and 2) the pointer will remain in'any given position. The hair-spring is then given an initial bias such that the pointer 52 rests at its lowermost travel position- (opposite zero) which is actually about one p.s.i. above zero position (atmospheric) within the Bourdon tube. Under this bias condition the hair-spring is fastened as at 86 and the link 71 should just fit the distance between holes 95-90.

The Bourdon tube elements 65, 70 are not balanced and are subject to vibration, harmonics etc. On the other hand the pointer assembly is balanced. It is this balance, plus the loop link 71, which prevents undesired movements of the Bourdon tube end from being transmitted to, and observed at, the pointer 52. The flexing of the loop 71 allows the Bourdon tube which is unbalanced to move or vibrate without afiFecting the pointer which isbalanced.

This application constitutes a division of our copending application S.N. 435,883, filed June 10, 1954, now Patent No. 2,885,536, which is a division of application Serial No. 176,382, filed July 28, 1950, now abandoned.

What we claim as new, and desire to secure by Letters Patent of the United States is:

1. A support structure for an illumination means providing interior illumination for a housing including, a housing having a side with several apertures therethrough, a plate for substantially parallel external cooperation with said side of said housing having said apertures, an incandescent source attached to said plate and extending through a first of said apertures into the housing interior,

prong members integral with said plate extending therefrom and into said housing interior by way of said first aperture and having hook portions engaging the interior of the housing side, and a resiliently expansible button spaced from said prongs extending from said 7 claimed in claim 1 wherein said hooked portions extend from said prongs respectively on the side of said prong members opposite from said resiliently expansible button.

3. A support structure for an. illumination means as claimed in claim 2 wherein said hooked portions are wedged shaped.

4. A support structure for an illumination means providing illumination for a scale of an indicating ins ment including, a housing for supporting the scale and having a side with several apertures therethrough, a plate means for substantially parallel external cooperation with the side of said housing, an incandescent source attached to said plate and extending through a first of said apertures into the housing interior to illuminate said scale, a pair of prong members fixed to said plate extending therefrom and into the housing interior by way Benjamin June 14, 1927 Eustice Sept. 10, 1929 

